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Automated Lipid Bilayer Membrane Formation Using a Polydimethylsiloxane Thin Film
Published on: July 10, 2016
Phase separation between phospholipids and grafted polymer chains onto a fluctuating membrane.
M Benhamou1, I Joudar, H Kaidi
1Laboratoire de Physique des Polymères et Phénomènes Critiques, Faculté des Sciences Ben M'sik, BP 7955, Casablanca, Morocco. m.benhamou@univh2m.ac.ma
The European Physical Journal. E, Soft Matter
|January 19, 2008
Summary
Membrane undulations enhance phase separation between phospholipids and polymer anchors, promoting separation at higher temperatures. This effect is more pronounced in membranes with lower bending rigidity, increasing domain size when polymer lengths vary.
Area of Science:
- Biophysics
- Materials Science
- Physical Chemistry
Background:
- Fluid membranes composed of phospholipids and grafted polymer chains can undergo phase separation.
- Phase separation is influenced by factors like temperature, pressure, and membrane environment.
- Polymer chains are anchored to the membrane via amphiphile lipid molecules.
Purpose of the Study:
- To theoretically investigate the phase separation (demixing transition) between phospholipids and grafted polymer chains on a fluid membrane.
- To develop a new approach incorporating membrane undulations into the phase separation model.
- To analyze the effect of polymer chain length distribution on domain formation.
Main Methods:
- Theoretical modeling of phase separation in lipid-polymer membranes.
- Incorporation of membrane undulations into the theoretical framework.
- Analysis of a fractal-form length distribution for anchored polymer chains.
Main Results:
- Membrane undulations induce attractive forces between anchors, accentuating phase separation at higher temperatures.
- Undulations contribute a positive segregation parameter (χm) scaling with inverse bending rigidity (κ⁻²).
- Polydispersity in polymer chain lengths increases the size of phospholipid- and anchor-rich domains.
Conclusions:
- Membrane undulations play a significant role in promoting phase separation, particularly in membranes with low bending rigidity.
- The findings provide quantitative insights into the factors governing lipid-polymer membrane organization.
- Understanding these phenomena is crucial for designing and controlling membrane properties in biological and artificial systems.
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